Explanation

Lego blocks are a popular building toy, which Cueball here uses to describe a philosophical conundrum: the distinction between a composition, and the collection of parts that make up that composition. For example, the Lego blocks he and his daughter, Ponytail, used to make a house are still around; they were put back into the bin, and can be used on future designs. However, the house itself, as a specific combination of those blocks, is gone. It ceased to exist when they took it apart. In essence, they "killed" the house.

Later in her life, Ponytail extends this thinking to humans and organ donation. The US has an opt-in system for organ donation; in the event that you die, any of your organs or tissues that remain functional after your death can be donated for transplantation or medical research, provided you've opted into the organ donor registry. Ponytail compares her organs to the Lego blocks she's carrying - even if she (the composition) dies, her organs (the pieces) can continue to serve another. As such, she is compelled to register as an organ donor.

The title text is the same question asked in the first panel, asked from this new perspective - instead of asking where the Lego house went, the questioner (presumably a young child, possibly still Ponytail) is asking where his/her Grandpa went. Humans are a composition of many parts; the parts are usually buried or cremated when we die, but the composition is something else entirely. What exactly happens to a human composition after death is a question for religious debate, but we know for sure it doesn't stay here.

Transcript

[Ponytail and her father Cueball are putting away Lego bricks.]

Cueball: When you take apart a Lego house and mix the pieces into the bin, where does the house go?

Ponytail: It's in the bin.

Cueball: No, those are just pieces. They could become spaceships or trains. The house was an arrangement. The arrangement doesn't stay with the pieces and it doesn't go anywhere else. It's just gone.

[Ponytail, older, is standing at a desk. She's holding a couple of Lego bricks.]

[She looks at the bricks.]

[She checks off a box next to the words "Organ Donor" on something on the desk.]

Anyone interested in the issues raised in this comic would do well to look up the problem of the Ship of Theseus.
108.162.216.53 17:03, 29 November 2013 (UTC)

For me, once you accept the fact of evolution, and therefore that all life on earth emerged from a common ancestor, it is patently obvious that the relevance of religion to what happens to my "composition" (self) after death is ... zero. To wit: "If you want to know what happens when you die, go look at some dead stuff." 108.162.219.223 01:22, 7 January 2014 (UTC)

The point of this comic is excellent, but it is dampened for me by the fact that Lego doesn't sell general-purpose blocks any more, it's all precision kit crap. Djbrasier (talk) 21:30, 23 January 2014 (UTC)

The first time I read this strip, I immediately thought back to one of my all-time favorite books. The basis of Unwind by Neal Shusterman is essentially the idea behind this strip, except from an opposite point of view. --Hammy2211 (talk) 21:34, 26 March 2014 (UTC)

The premise of Unwind is that the future American culture has decided to believe that if a person's tissues are all transported into new people, the donor is then still alive, and therefore it is ok to "unwind" unwanted teenagers, since they are still "alive," just in another state of life. Obviously, the teenagers chosen to be unwound aren't ok with this view. Dystopian novels are fun. This is one you won't forget quickly. 108.162.245.135 19:51, 12 December 2015 (UTC)

I disagree with this interpretation of the comic. I think ponytail is marking the box with a combination between a checkmark and an X mark, which in a test (where I live at least) means 'partially correct'. It is usually drawn as a check mark with the LONGER arm being one of the two lines of the X, but here, the SHORTER arm and PART of the longer arm seem to form the top half of the X. This makes me not sure that this was the actual intention, but I still think it was.
Now, I think ponytail in part wants to help others with her parts just like the current explanation says, but I also think she's afraid of making herself disappear while doing so. If she isn't an organ donor, she will stay complete and will continue to exist, but if she is a donor, then the arrangement will be gone and SHE will be gone forever. --NeatNit (talk) 15:12, 14 July 2014 (UTC)

I interpreted the unsual check mark as either a tick which had been turned to a cross, or a mix between a cross and tick. I also read the title text as a suspicious child questioning whether Grandpa has been taken apart or something similar. --Pudder (talk) 09:02, 24 October 2014 (UTC)

I agree. It seems awfully strange that after being told that she's 'disappear' she'd go and disassemble herself... 141.101.98.252 10:08, 17 December 2014 (UTC)

Then again, organ donation only occurs after death (well, legally) so she's going to end up "disassembled" no matter what she picks there if she's dead (by decay or incineration or whatever). In fact, you could say that as soon as you die your body begins to disassemble. -Pennpenn 108.162.250.155 04:42, 11 February 2015 (UTC)

I thought she was crossing out the box, indicating that she would like to exist for as long as possible, and would not like to disrupt her "organization" through organ donation. 173.245.54.20 20:13, 7 November 2015 (UTC)

It's a bureaucracy. If there's only one checkbox, you generally leave it empty if you don't want to do it, or fill it in (with a checkmark or an X) if you want to do it. If I saw a box like that with a checkmark in it, I would interpret it exactly the same as I would a box with an X in it. No-one at DEQ actually would expect people in general to be able to follow directions as complex as 'checkmark to say yes, X to say no.' Not only are there people who don't have very good English skills, there are a bunch of people who don't actually bother to read directions at all, so they are smart to keep it simple. 108.162.245.135 19:42, 12 December 2015 (UTC)

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